In Ott M. et al.: ‘An architecture for adaptive QoS and its application to multimedia systems design’, Computer Communications, Elsevier Science Publishers BV, Amsterdam, NL, Vol. 21, No. 4, 10 Apr. 1998, pages 334-349, there is described an architecture for adaptive QoS and its application to multimedia system design, wherein the concept of QoS is applied to all layers of a software architecture. Each layer deals with QoS at its appropriate level of abstraction using a generic application interface for communicating QoS parameters.
Further, in Landfeldt B. et al.: ‘User Service Assistant: an end-to-end reactive QoS architecture’, Quality of Service, 1998(IWQOS 98), 1998 Sixth International Workshop on NAPA, Calif., USA, 18-20 May 1998, New York, N.Y., USA, IEEE, U.S. 18 May 1998, pages 177-186, there is described a framework for QoS management which is reactive and has a non-layered structure. The concept outlined focuses on providing assistance in decision making to a user, rather than automating the entire process of resource reservation and renegotiation.
Further, in US 2001/0055971 A1, there is described a method for radio access bearer reconfiguration in a communication system having a core network and user equipment coupled to a radio network controller. When the core network establishes a service with the user equipment, a radio access bearer is set up for that service including certain parameters that effect the quality of service. The radio network controller may then determine that one or more of the radio access bearer parameters need to be modified.
Further, in Le Bodic G. et al. ‘Dynamic 3G network selection for increasing the competition in the mobile communications market’, Vehicular Technology Conference, there is described a dynamic 3G network selection for increasing the competition in a mobile communications market, where a service provider, a network operator and a user have ability to trade communication services. For this purpose, there is specified a middleware in which software agents can supply or purchase QoS contracts.
Numerous factors associated with technology, business, regulation and social behavior have driven the spreading of mobile multimedia applications in the past, i.e. mobile applications that can deal with voice, image, text data, etc. Existing solutions to mobile multimedia applications rely on a single connection such as a TCT/IP connection and therefore focus on an integrated bearer service enabling the transfer of multimedia data over only a single TCT/IP connection.
The particular deficiency of this approach is that different multimedia data have different attributes, i.e. voice data may be characterized as real time data requiring a low band width, while image data may be transferred in a non-real time mode, however, involving an increased amount of data. Therefore, this approach is inherently inflexible in view of different characteristics of different multimedia services.
Another problem is non-compliance with future network architectures where an endpoint—i.e. a mobile device like a mobile telephone, personal digital agent PDA, or laptop computer—has the option to use parallel or equivalently multiple connections in a heterogeneous wireless network for supporting different applications running simultaneously at the mobile endpoint.